Anxiety is a fundamental emotion and a normal response in some warm-blood animals including human, which is characterized by an apprehensive uneasiness of mind usually associated with an impending or anticipated experience that may be problematic. When such apprehension becomes disproportionate and overwhelming, it is termed an anxiety neurosis which can be characterized by helplessness, tension, uneasiness, faintness or even panic syndrome. This anxiety status can also be accompanied by physiological signs such as heart palpitation, gasping, sweating, dry mouth and nausea. The mechanism by which anxiety is induced in the Central Nervous System (CNS) is complex (Haefely W., Psychopharmacology of Anxiety, Eur. Neuropsychopharmacol., Vol. 1, pp. 89-95, 1991).
Anxiety and depressive disorders are the most common psychiatric diseases. Both are known to be associated with major impairment and adverse consequences in later life. Estimates of the prevalence of any childhood anxiety disorder are in the order of 3 to 12% and rise to as high as 40% or over and most of impairment is not required for a diagnosis. In general, epidemiological studies show that rates of any anxiety disorders are higher in children than adolescents. In contrast, rates of depressive disorder in young people show higher rates in adolescence than in childhood. Depression and anxiety in childhood and adolescence have long-term deleterious outcomes for a significant proportion of young people. Depression and anxiety, once experienced in childhood are very likely to recur in adulthood. Early onset of depressive and anxiety are also associated with substantial social impairment. Even sub-clinical levels of depression in children and adolescents are associated with significant morbidity in the form of psychosocial impairment and service utilization. Furthermore, adolescents identified as having high levels of depressive or anxiety symptoms are significantly more likely to experience depressive disorder in adulthood than adolescents with depression levels within the normal range. The observations that sub-clinical symptoms of depression are associated with significant morbidity rate and those high level of depression and anxiety symptoms predict depressive and anxiety disorders together with the evidence that depression and anxiety can be regarded as continua (Costello E J et al., The Great Smoky Mountains Study of Youth, Goals, design, methods, and the prevalence of DSM-III-R disorders, Arch Gen Psychiatry, 53, pp. 1129-1136, 1996).
Specifically, anxiety symptoms or disorders frequently precede depressive symptoms or disorders. Moreover although certain sub-types of anxiety, namely social phobia and panic rarely precede depression, individuals with those disorders and depression are very likely to have had a different anxiety disorder that predated the onset of depression.
Anxiety disorders are the most common diseases among psychiatric illnesses. It is severed to leave the patient dysfunctional. In addition to the subjective feeling of anxiety and panic, physiological changes such as tachycardia, palpitations, sweating and trembling are reported. Secondary insomnia is commonly observed in patients with anxiety, with complaints of difficulty in getting to sleep and of frequent walking from sleep. Symptoms of anxiety often accompany withdrawal from sedatives, or may arise from the use of stimulants such as amphetamines. It is reported that lactate infusion and hyperventilation produce subjective symptoms and objective signs of anxiety, and are associated with decreased vagal tone, i.e., decreased parasympathetic activity (George et al., Arch. Gen. Psych., 46, pp. 153-156, 1989).
There remain several requirements as an ideal anti-anxiety medicine such that it should not cause sleepiness and should keep patient calm without physical and spiritual problems.
At present, benzodiazepine, diazepam, oxazepam, prazepam, lorazepam, alprazolam, helazepam and clonazepam are extensively used as representative anti-anxiety drugs, most of which induce sedation and sleepy syndrome (YOON D. J., A side effect of psychiatric drug, Journal of Korean Medical Association, 38(10), pp. 1196-1202, 1995). It has been reported that benzodiazepine, most frequently used anti-depressant drug in spite of their side-effects such as sedation, muscle-relaxation, amnesia, and dependence etc, increases the affinity for GABA receptor, a major inhibitory transmitter in the CNS (Central Nervous System) to induce the influx of Cl− ions into the cells. The development of new anti-anxiety agent without other side effects such as addition, withdrawal syndrome, and so on has been still needed till now. (Mary J. et al., Pharmacology 2nd edition, Lipincott Williams & Wilkins, pp. 89-93, 2000).
Magnolia obovata has been traditionally used as stomachics and the leave thereof has been reported to be edible in Asian countries such as Korea and Japan. There has been also reported that the plant contains various ingredients such as β-eudesmol, β-pinene, magnolil and honokiol (Chung B. S. and Shin M. K., HyangyakDaesacheon, Youngrimsa, pp. 469-471, 1998).
However, there have been no disclosure or suggestion that ovobatol isolated from the extract of Magnolia obovata shows anti-anxiety activity in any of above cited literatures, the disclosures of which are incorporated herein by reference incorporated herein.